At Vandenberg Air Force Base, the Aquarius/SAC-D spacecraft is undergoing Limited Performance Tests including the SAC-D service platform, the Aquarius science instrument, and the SAC-D instruments.

At NASA's Space Launch Complex 2, the Delta II second-stage propulsion system qualification testing is under way. First-stage propulsion system qualification testing is scheduled for next week.

The Aquarius/SAC-D mission is a collaboration between NASA and Argentina's space agency with participation by Brazil, Canada, France and Italy. NASA's Launch Services Program at the Kennedy Space Center in Florida is managing the launch. United Launch Alliance of Denver, Colo., is NASA's launch service provider of the Delta II 7320.

The spacecraft had been shipped from Lockheed Martin Space Systems in Denver. It was offloaded from the aircraft and taken to the Astrotech payload processing facility located near Kennedy Space Center. On April 9, it was moved inside the processing high bay, the lid to the shipping container was lifted from over the spacecraft, and the protective wrap surrounding it was removed.

On April 11, Juno was lifted onto a rotation and test fixture and rotated from the vertical to horizontal configuration so that electrical testing could begin. Initial testing now is under way. Antenna installations, including the high gain antenna, begin April 20.

The solar-powered Juno spacecraft will orbit Jupiter's poles 33 times to find out more about the gas giant's origins, structure, atmosphere and magnetosphere.